RESEARCH ARTICLE Challenges in EGFRvIII Detection in Head and Neck Squamous Cell Carcinoma

Objective Head and neck squamous cell carcinoma (HNSCC) accounts for more than 5 % of all can-cers worldwide. The mortality rate of HNSCC has remained unchanged (approximately 50%) over the last few decades. Ubiquitous overexpression of wild type EGFR in many solid tumors has led to the development of EGFR targeted therapies. EGFR can be consti-tutively activated via several mechanisms including the truncated, EGFR variant III isoform (EGFRvIII). EGFRvIII lacks exons 2–7 and has been reported to be present in up to 20– 40 % of HNSCC. EGFRvIII has been shown to contribute to cetuximab resistance. The mechanisms leading to EGFRvIII expression in HNSCC are unknown. The present investi-gation was undertaken to determine the etiology of EGFRvIII in HNSCC. Materials and Methods Fixed HNSCC and glioma tissues were analyzed by fluorescence in situ hybridization for EGFR amplification. DNA and RNA from fresh frozen specimens were used to determine the presence of EGFRvIII transcripts and the mechanisms of expression via PCR, RT-PC